Mindia Matidia or Matidia Minor (Minor Latin for the younger, 85-after 161) was related to several important ancient Roman Emperors. The modern village of Matigge Italy, is named after her.

Matidia Minor was the daughter of Salonia Matidia from her second marriage to the otherwise unattested Roman aristocrat Lucius Mindius. Her mother was a niece of the Roman emperor Trajan. Her half-sister Vibia Sabina was to become empress and wife of the Roman emperor Hadrian. Hadrian was also her third cousin.

After her father’s death in 85, Matidia along with her half-sisters lived with their grandmother and mother and were raised in the household of Trajan, his wife Plotina and her stepfather. Matidia Minor never received the title of Augusta, nor did she ever marry or have any children (which was unusual at the time). Yet she was a very wealthy, cultured, and influential woman.

Trajan gave her a villa where modern Matigge, Italy is now located. Due to this villa, the city became known in Latin as Insula Matidiae (modern Matigge, Italy). Matidia became competent in her affairs and when her sister became empress, she would often travel with her and her brother-in-law. Matidia underwrote the restoration of the theatre of Sessa Aurunca which was probably damaged by an earthquake during the rule of Emperor Antoninus Pius (138-161). Her generosity was commemorated with a statue here.

Matidia lived to an advanced age and outlived most of her relatives. In her later years, she was very close to her great-nephew, the future emperor Marcus Aurelius, and his family. Marcus Aurelius would sometimes allow his daughters to stay with his great-aunt.

Matidia, like many other childless women, "attracted a number of hangers-on who hoped to be remembered in her will". On her deathbed, they sealed her codicils (additions to her will) assuring their validity and ensuring that they would inherit some of her substantial estate. From her will, various family members and associates received a million sesterces (an ancient Roman unit of currency), her estate, and various other items she had. The administrator of the estate was the empress Faustina the Younger.